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[[تصویر:Island_near_Fiji.jpg|thumb|300px|[[فجی]] کے قریب ایک چھوٹا جزیرہ]]
خشکی کا ایسا ٹکڑا جو چاروں جانب سے پانی سے گھرا ہوا ہو۔
خشکی کا ایسا ٹکڑا جو چاروں جانب سے پانی سے گھرا ہوا ہو۔ بہت چھوٹے جزائر جیسا کہ پانی میں ابھرتے ہوئے زمینی خدوخال کو مرجانی جزیرہ (Atoll) یا ٹاپو (Islet) کہتے ہیں۔ جزائر کی دو اقسام ہوتی ہیں ایک بر اعظمی جزائر اور دوسرے سمندری جزائر۔
بر اعظمی جزائر وہ جزیرے ہوتے ہیں جو بر اعظمی تختے (Continental Shelf) پر واقع ہوں، مثال کے طور پر [[گرین لینڈ]]، [[ٹرینیڈاڈ و ٹوباگو]]، [[برطانیہ]]، [[آئرستان]] اور [[صقلیہ]]، [[سماٹرا]]، [[بورنیو]] اور [[جاوا]] اور [[نیو گنی]] و [[تسمانیہ]] وغیرہ۔
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سمندری جزائر وہ جزیرے ہوتے ہیں جو کسی بر اعظمی تختے پر واقع نہيں ہوتے۔ ان میں آتش فشانی جزائر اکثریت کے حامل ہیں۔
[[زمین]] پر مصنوعی جزائر بھی پائے جاتے ہیں۔ جزائر کے مجموعے کو [[مجموعہ الجزائر]] (Archipelago) کہتے ہیں۔
[[Image:Ailsa Craig from Waverley.jpg|thumb|220px|right|[[Ailsa Craig]], an ancient volcanic plug off the south-west coast of [[Scotland]]]]
[[Image:Island near Fiji.jpg|right|thumb|200px|A small [[Fiji]]an island.]]
[[Image:Island.jpg|right|thumb|200px|A small island in the [[Adriatic Sea]]]]An '''island''' ({{IPAEng|ˈaɪlənd}}) or '''isle''' ({{IPA|/ˈaɪl/}}) is any piece of land that is completely surrounded by water, above high tide, and isolated from other significant landmasses. Very small islands such as emergent land features on [[atoll]]s are called '''[[islet]]s'''. A '''key''' or [[cay]] is another name for a small island or islet. An island in a river or lake may be called an [[ait|eyot]], {{IPA|/ˈaɪət/}}.
There are two main types of islands: '''continental islands''' and '''oceanic islands'''. There are also [[artificial island]]s. A grouping of geographically and/or geologically related islands is called an [[archipelago]].
ان کے علاوہ [[زمین]] پر منطقۂ حارہ کے جزائر (Tropical Islands) بھی ہوتے ہیں جن میں [[مالدیپ]]، [[ٹونگا]]، [[ناؤرو]] اور [[پولینیشیا]] وغیرہ معروف ہیں۔
The word ''island'' comes from [[Old English]] ''ī(e)gland'' (literally, "watery land"). However, the spelling of the word was modified in the 15th century by association with the [[Etymology|etymologically]] unrelated Old French loanword ''isle''.<ref>{{cite web |url=http://dictionary.reference.com/browse/Island |title=Island |accessdate=2007-03-05 |publisher=[[Dictionary.com]]}}</ref>
==متعلقہ مضامین==
There is no standard of size which distinguishes islands from [[islet]]s and [[continent]]s.
*[[مجموعہ الجزائر]]
*[[جزائر نخیل]]
When defining islands as pieces of land that are completely surrounded by water, narrow bodies of water like [[river]]s and [[canal]]s are generally left out of consideration{{Fact|date=February 2007}}. For instance, in France the [[Canal du Midi]] connects the [[Garonne]] river to the [[Mediterranean Sea]], thereby completing a continuous water connection from the [[Atlantic Ocean]] to the Mediterranean Sea. So technically, the land mass that includes the [[Iberian Peninsula]] and the part of France that is south of the Garonne River and the Canal du Midi is completely surrounded by water. For a completely natural example, the [[Orinoco]] River splits into two branches near Tamatama, in Amazonas state, Venezuela. The southern branch flows south and joins the Rio Negro, and then the Amazon. Thus, all of the Guianas (Guyana, Suriname, and French Guiana) and substantial parts of Brazil and Venezuela are surrounded by (river or ocean) water. These instances are not generally considered islands.
This also helps explain why Africa-Eurasia can be seen as one continuous landmass (and thus technically the biggest island): generally the [[Suez Canal]] is not seen as something that divides the land mass in two.
On the other hand, an island may still be described as such despite the presence of a land bridge, e.g., [[Singapore]] and its causeway or the various Dutch delta Islands, such as [[IJsselmonde (island)|IJsselmonde]]. The retaining of the island description may therefore be to some degree simply due to historical reasons - though the land bridges are often of a different geological nature (for example sand instead of stone), and thus the islands remain islands in a more scientific sense as well.
==Types==
=== Continental islands ===<!-- This section is linked from [[Great Barrier Reef]] -->
[[تصویر:Angelskyview.jpg|thumb|left|[[Angel Island, California|Angel Island]] in the San Francisco Bay]]
Continental islands are bodies of land that lie on the [[continental shelf]] of a continent. Examples include [[Greenland]] and [[Sable Island]] off [[North America]]; [[Barbados]] and [[Trinidad]] off [[South America]]; [[Great Britain]], [[Ireland]] and [[Sicily]] off [[Europe]]; [[Sumatra]] and [[Java (island)|Java]] off [[Asia]]; and [[New Guinea]], [[Tasmania]] and [[Kangaroo Island]] off [[Australia]].
A special type of continental island is the '''microcontinental island''', which results when a continent is [[rift (geology)|rifted]]. Examples are [[Madagascar]] off [[Africa]]; the [[Kerguelen Islands]]; and some of the [[Seychelles]].
Another subtype is an island or [[shoal|bar]] formed by deposition of tiny rocks where a water current loses some of its carrying capacity. An example is [[barrier island]]s, which are accumulations of [[sand]] deposited by sea currents on the continental shelf. Another example is islands in [[river delta]]s or in large rivers. While some are transitory and may disappear if the volume or speed of the current changes, others are stable and long-lived.
=== Oceanic islands ===
[[تصویر:Hawai'i.jpg|right|thumb|The islands of [[Hawaii (island)|Hawai'i]] are volcanic islands.]]
[[تصویر:Wake Island.png|right|thumb|[[Wake Island]] is a volcanic island that has become an [[atoll]].]]
Oceanic islands are ones that do not sit on continental shelves. They are [[volcano|volcanic]] in origin. One type of oceanic island is found in a '''volcanic island arc'''. These islands arise from volcanoes where the [[subduction]] of one plate under another is occurring. Examples include the [[Mariana Islands]], the [[Aleutian Islands]] and most of [[Tonga]] in the [[Pacific Ocean]]. Some of the [[Lesser Antilles]] and the [[South Sandwich Islands]] are the only Atlantic Ocean examples.
Another type of oceanic island occurs where an [[oceanic rift]] reaches the surface. There are two examples: [[Iceland]], which is the world's largest volcanic island, and [[Jan Mayen]] — both are in the Atlantic.
A third type of oceanic island is formed over volcanic [[Hotspot (geology)|hotspots]]. A hotspot is more or less stationary relative to the moving [[tectonic plate]] above it, so a chain of islands results as the plate drifts. Over long periods of time, this type of island is eventually eroded and "drowned" by [[isostasy|isostatic adjustment]], becoming a [[seamount]]. Plate movement across a hot-spot produces a line of islands oriented in the direction of the plate movement. An example is the [[Hawaiian Islands]], from [[Hawaii]] to [[Kure Atoll|Kure]], which then extends beneath the sea surface in a more northerly direction as the [[Emperor Seamounts]]. Another chain with similar orientation is the [[Tuamotu Archipelago]]; its older, northerly trend is the [[Line Islands]]. The southernmost chain is the [[Austral Islands]], with its northerly trending part the atolls in the nation of [[Tuvalu]]. [[Tristan da Cunha]] is an example of a hotspot volcano in the Atlantic Ocean. Another hot spot in the Atlantic is the island of [[Surtsey]], which was formed in 1963.
An atoll is an island formed from a [[coral reef]] that has grown on an eroded and submerged volcanic island. The reef rises to the surface of the water and forms a new island. Atolls are typically ring-shaped with a central [[lagoon]]. Examples include the [[Maldives]] in the [[Indian Ocean]] and [[Line Islands]] in the Pacific.
== See also ==
{{commons|Island}}
*[[Desert island]]
*[[High island]]
*[[Insularity]]
*[[Island biogeography]]
*[[Island country]]
*[[Islescape]]
*[[Islomania]]
*[[List of artificial islands]]
*[[List of divided islands]]
*[[List of fictional islands]]
*[[List of islands]]
*[[List of islands by area]]
*[[List of islands by name]]
*[[List of islands by highest point]]
*[[List of islands by population]]
*[[Phantom island]]
*[[Private island]]
*[[Reef]]
*[[Skerry]]
*[[Small Island Developing States]]
*[[Tidal island]]
== References ==
<div class="references">
<references />
</div>
== External links ==
{{Wikisource1911Enc|Island}}
*[http://www.un.org/Depts/los/convention_agreements/texts/unclos/part8.htm Definition of island] from [[United Nations Convention on the Law of the Sea]]
*[http://islands.unep.ch/isldir.htm Listing of islands] from [[United Nations]] Island Directory.
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[[ar:جزيرة]]
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